New Study: Whole Milk's Surprising Benefit

Fat has been getting a bad rap for a while. Why else do we have a fridge full of alternatives (2 percent, skim, almond, coconut and soy, just to name a few) for our families? Whatever happened to just buying a gallon of milk in all its full-fat glory?

Kids who drank one cup of whole milk per day had comparable levels of vitamin D as kids who drank nearly three cups of 1% milk per day.
However, kids who drank whole milk had a lower BMI by 0.79 points—so the higher the fat content of the milk they were given, the lower their BMI. This is one factor in lowering childhood obesity rates. The Canadian researchers who did the study suggest that vitamin D is better absorbed in the body with higher-fat milk, and drinking low-fat milk could actually leave kids hungry for calorie-dense food.

A study published in Circulation earlier this year showed that there's also definitely more to the "whole milk is bad for you" narrative. Actually, the research results found people who consume full-fat dairy are less likely to develop diabetes.

Dr. Dariush Mozaffarian, dean of Tufts Friedman School of Nutrition Science & Policy, and his colleagues found that those who had higher levels of three different by-products of full-fat dairy had (on average) a 46 percent lower risk of developing diabetes.

“I think these findings together with those from other studies do call for a change in the policy of recommending only low-fat dairy products,” Mozaffarian told Time magazine. “There is no prospective human evidence that people who eat low-fat dairy do better than people who eat whole-fat dairy.”

Kids who drank one cup of whole milk per day had comparable levels of vitamin D as kids who drank nearly three cups of 1% milk per day. And they had a lower BMI than kids who drank low-fat milk, too.

The case against low-fat dairy

U.S. dietary guidelines recommend consuming less than 10 percent of calories from saturated fatty acids. But as CBS News points out, a latte made with one cup of whole milk can already contain a quarter of the daily total.

The thought process behind avoiding whole milk is that full-fat dairy products contain more calories. Yet studies show that people who avoid fat tend to compensate with sugar or carbs (both can worsen the effects on insulin and diabetes risk).

Actually, a separate women's health study even found that participants who consumed high-fat dairy products had an 8 percent lower risk of being overweight or obese.

“This is just one more piece of evidence showing that we really need to stop making recommendations about food based on theories about one nutrient in food,” Mozaffarian said. “It’s crucial at this time to understand that it’s about food as a whole, and not about single nutrients.”

So how does whole fat help lower risk of diabetes?

It's not super clear what exactly is at play here. There's that idea we mentioned above about how high-fat dairy can mean people are more likely to be full and less likely to find additional calories with high-carb and high-sugar foods. Time magazine also points out that "the fats in dairy may be acting directly on cells, working on the liver and muscle to improve their ability to break down sugar from food." There's even the possibility that microbes in fermented, high-fat dairy foods (e.g. cheese) help improve insulin response.

The studies don't say to completely ditch the skim milk and drink only whole milk. But they are saying food decisions are a lot more complex than choosing one exclusive nutrient over another. Once you realize that variety is key, as Barney Stinson says, it's going to be legen- ... wait for it ... dairy!